So, I tore down my top end tonight on my 2006 YZ250F. My cams looked good, but then I removed the cylinder, and had scoring and a burn mark on the back side of the piston, and scoring on in the cylinder. e Also, where the connecting rod connects to the crank, there is some "blueing". You will see that in the pics below. What does that mean? Side note, when I took the cams out, I checked the valve clearance. On hte intake valves, I couldn't even get a .05 mm feeler to fit. The exhaust valves seemed fine. I'm wondering what my options are? Do I need a new cylinder? Here's some pics: I'm looking for advice...Am I just screwed on this? If I can find a cylinder, do I need to do anything to the bottom end? Thanks.